According to the Financial Times, Mr Blair is keen to take up roles in the private sector and his first assignment will be to provide JPMorgan with political and strategic advice.
Mr Blair's contribution to the company would be "enormously valuable", Jamie Dimon, JPMorgan's chief executive, said.
"There are only a handful of people in the world who have the knowledge and relationships that he has," Mr Dimon noted.
He claims to have made a personal visit to see the former prime minister and the pair "hit it off".
Mr Blair told the FT: "I have always been interested in commerce and the impact of globalisation. Nowadays, the intersection between politics and the economy in different parts of the world, including the emerging markets, is very strong."
Washington lawyer Robert Barnett brokered the job and he claimed that Mr Blair was approached by "more than half a dozen financial services companies" after he resigned as British leader.
This news comes after Mr Blair's former chief of staff, Jonathan Powell, joined Morgan Stanley last month.